Research Findings Expected to Ease Treatment of Low Neutrophil Counts in Cancer Patients
Multicenter trial led by St. Jude Children's Research Hospital investigators may change neutropenia treatment for all childhood cancer patients
MEMPHIS, Tenn., March 10 /PRNewswire-USNewswire/ -- For patients
like 10-year-old Sabrina Jo Spence, new research led by St. Jude
Children's Research Hospital investigators meant fewer injections
to combat the drop in white blood cells following her recent
chemotherapy.
"Cool," Sabrina told Sheri Spunt, M.D., an associate member of
the St. Jude Department of Oncology, after hearing the news and
breaking into what Sabrina called her "happy dance." Sabrina is
battling rhabdomyosarcoma.
Spunt is Sabrina's doctor and lead author of a study expected to
transform how children like Sabrina are treated for neutropenia.
Neutropenia is the dangerous drop in white blood cells that leaves
cancer patients at increased risk for infections and can delay
chemotherapy. The work appears in the March 10 edition of the
Journal of Clinical Oncology.
In a study of 44 young cancer patients, investigators reported
that the drugs pegfilgrastim and filgrastim were similarly safe and
effective at restoring a safe level of neutrophils following
chemotherapy. But pegfilgrastim treatment required a single
injection, while filgrastim involved daily injections for a week or
longer. The trial was a multicenter, randomized, open-label study
to evaluate the safety and efficacy of the two drugs as well as how
they are used and metabolized in the body.
"This study will make a big impact on the quality of life for
patients and their families," Spunt said.
Both drugs are synthetic growth factors designed to stimulate
production of neutrophils. Neutrophils are made in the bone marrow
and protect against bacterial and fungal infections. They are often
short-term casualties of chemotherapy. Filgrastim has been widely
used to speed neutrophil recovery. Pegfilgrastim was developed as a
longer-acting version of filgrastim. It is approved for use in
adults.
Although the study focused on patients with sarcomas such as
rhabdomyosarcoma and Ewing sarcoma, Spunt said the results will
likely change neutropenia treatment for all childhood cancer
patients. The study's participants ranged in age from 28 days to 21
years.
"A large percentage of childhood cancer patients get growth
factor support during their therapy," Spunt explained. "The
injections are painful for patients and difficult for parents,
especially the parents of young children who often need two adults
to administer the drug daily. The burdens of therapy for them are
considerable."
Sabrina, who did not participate in this study, said she became
accustomed to the daily shots administered by her grandmother,
Alice Spence. But Sabrina always held tight to her mother's hand
when the time came. She was happy when the daily injections were
replaced by a single shot.
In the study, researchers reported that after the first round of
chemotherapy with vincristine, doxorubicin and cyclophosphamide,
neutrophil levels started to rise in half the patients five days
after treatment with pegfilgrastim, compared with six days for the
filgrastim group. By the third round of chemotherapy, which
followed additional treatment with ifosfamide and etoposide, half
the patients in both groups were improving in seven days.
Both pegfilgrastim and filgrastim are made by Amgen, a
California-based pharmaceutical company. Filgrastim is metabolized
in the kidneys. Pegfilgrastim includes a polyethylene glycol tail
and is broken down by neutrophils. As a result, pegfilgrastim
levels drop as the patient's neutrophils climb.
The other authors of this paper are Helen Irving (Royal
Children's Hospital, Queensland, Australia); Jami Frost (Lovelace
Health Plan, Albuquerque, N.M.), Leonard Sender (CHOC Children's
Hospital, Orange, CA.), Matthew Guo, Bing-Bing Yang, Lyndah
Dreiling (Amgen Inc.) and Victor Santana (St. Jude).
This work is supported in part by Amgen, the National Cancer
Institute and ALSAC.
St. Jude Children's Research Hospital
St. Jude Children's Research Hospital is internationally
recognized for its pioneering research and treatment of children
with cancer and other catastrophic diseases. Ranked the No. 1
pediatric cancer hospital by Parents magazine, St. Jude is the
first and only National Cancer Institute-designated Comprehensive
Cancer Center devoted solely to children, and has treated children
from all 50 states and from around the world. St. Jude has
developed research protocols that helped push overall survival
rates for childhood cancer from less than 20 percent when the
hospital opened to almost 80 percent today. St. Jude is the
national coordinating center for the Pediatric Brain Tumor
Consortium and the Childhood Cancer Survivor Study. In addition to
pediatric cancer research, St. Jude is also a leader in sickle cell
disease research and is a globally prominent research center for
influenza.
Founded in 1962 by the late entertainer Danny Thomas, St. Jude
freely shares its discoveries with scientific and medical
communities around the world, publishing more research articles
than any other pediatric cancer research center in the United
States. St. Jude treats more than 5,400 patients each year and is
the only pediatric cancer research center where families never pay
for treatment not covered by insurance. St. Jude is financially
supported by thousands of individual donors, organizations and
corporations without which the hospital's work would not be
possible. For more information, go to www.stjude.org.
Source: St. Jude Children's Research Hospital
CONTACT: Summer Freeman, (desk) +1-901-595-3061, (cell)
+1-901-297-9861,
summer.freeman@stjude.org;
or Carrie Strehlau, (desk) +1-901-595-2295, (cell)
+1-901-297-9875, carrie.strehlau@stjude.org,
both of St. Jude Children's
Research Hospital
Web Site: http://www.stjude.org/
Posted: March 2010
